Electric control and indication of point operating mechanisms for railways and the like



Nov. 9, 1937. R M, MacGREGOR ET AL 2,098,707

ELECTRIC CONTROL AND INDICATION OF POINT OPERATING MECHANISMS FOR RAILWAYS AND THE LIKE Filed April 9, 1955 G E A P R I N l l 4 Z5 Z5 550 N I 19 Q i 20 24x 18 V 8 i @1 0 l u/vomzcr/o/v/rz 4 fCE/W-R/FQ HL l OPE/PFTED 5 48. I "1' 42 Y 6M i I :40+-

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T.: J V Y 7 INVENTORS Roderick MaPc'usMacGmgan cmd Dazzqlas Goldie Ship THEIR ATTORNEY Patented Nov. 9, 1937 ELECTRIC CONTROL AND INDICATEON OF POINT OPERATING MECHANISMS FOR RAILWAYS AND THE LIKE Roderick Marcus MacGregor and Douglas Goldie Shipp, London, England, assignors, by mesne assignments, to The Union Switch & Signal Company, Pennsylvania Swissvale, Pa., a corporation of Application April 9, 1935, Serial No. 15,378 In Great Britain April 27, 1934 6 Claims.

This invention relates to the electric control and indication of point operating mechanisms for railways and the like of the kind in which the point machine or other mechanism for effecting the setting of the points is arranged to be operated by direct current supplied from the point of control through a pair of line wires which may also be utilized for the purpose of indicating the setting of the points by means of an alternating current transmitted from the points to the point of control.

The invention has for its object to provide improved arrangements for control and indication of this character and according to the principal feature of the invention the operation of the point machine or its equivalent is arranged to be under the sole control of a polarized single arm control relay located at the points, this relay being normally deenergized so long as the position of the points fully corresponds to that of the point lever or its equivalent at the point of control, any Want of correspondence in this respect due either to the reversal of the point lever or its equivalent to set the points from one position to the other or to an unintentional displacement of the points from either position being arranged to cause the control relay to be energized so as to efiect the supply of operating current to the point machine.

The apparatus of our invention is an improvement over that disclosed in the copending application Serial No. 323,286, filed December 3, 1928, by Lester E. Spray for Multiple control apparatus.

The invention is illustrated by way of example in the accompanying drawing the single figure of which is a diagrammatic view of a point operating mechanism provided with control and indication arrangements embodying one form of the invention.

Referring now to the drawing it will be seen that the point of control G and the point operating mechanism P are arranged to be connect-ed by a pair of control line conductors l, 2 and an indication line conductor 3. At the point of control a point lever 4 is provided adapted when in its normal extreme position N as shown to close contacts 5, ii and when in its reverse extreme position R to close contacts 1, 8, the lever 4 being also adapted to maintain a contact 9 closed during its movement from the N position to an intermediate position A and to maintain a contact H3 closed during its movement from the position R to an intermediate position E.

The point operating mechanism P which forms a part of the switch movement SM controlling the track switch S, comprises a point operating tact arm I6 is arranged to cooperate with two contact segments H, M which overlap each other to a considerable extent so that the contact arm It is in engagement only with one segment or the other when the points arefully set into a corresponding normal or reverse position, While 1 when the points are in an intermediate position the contact arm I6 is in engagement with both contact segments ll, iii. The segments l'|, l'8 are connected to the line conductor I through rectifiers I9, 20 respectively, the two rectifiers being oppositely arranged as shown so that when the point lever 4 is in its normal position N, for example, and the points are also in their corresponding full normal positions, the rectifier 19 connected to the contact segment I! which is in engagement with the contact arm IE or" the circuit controller V will prevent the flow of current from the line conductors I, 2 through the control relay winding I3. The control relay 0 will thus under these conditions be deenergized but in the event of the point lever t being moved to its reverse position R so as to reverse the polarity of the line conductors l, 2 the rectifier l9 will permit the fiow of current through the relay winding 13 which will thus be energized.

Furthermore, in the event of the points being displaced from their normal settings while the point lever 4 is in its normal position, the contact arm it of the circuit controller V will engage with both contact segments I? and I8 and current will thus be supplied to the relay winding I3 through the other connected rectifier 2|].

It will thus be seen that any want of correspondence between the position of the point lever 4 and the setting of the points will effect the energization of the control relay 0 by current 01 one polarity or the other according to whether the point lever 4 is in its normal or reverse position.

The movable contact 2! of the control relay O is directly connected to the line conductor l and is arranged to engage with one 'or the other of two fixed contacts .22, 23 which are connected through reverse and normal switches UN, UR operated by the circuit controller V to the ter'- minals of the field winding |2 of the point operating motor M. The terminals of the field winding |2 are connected through oppositely connected rectifiers. 24, to one terminal of the motor armature II the other terminal of which is connected to the line conductor 2.

The switches 'UR. and 'UN comprise movablef vsegment 29 only when the points are in;.the ir' full reverse position. V V V The operation of the apparatus as so far described is as follows:; 7 V V Assuming that the point lever 4 is in its nor- V mal position N and the points are in their full normal setting, the control relay 0 will be deenergized as above explained and if new the point lever is moved to its R. position to reverse the setting of the points, a circuit will be completed from the positive terminal of a source of supply of direct current through lever contact, I, V

line conductor 2, wire l4, relay winding |3, wire l5; contact arm l6 of circuitcontroller V, contact segment |I, rectifier l9, line conductor l,

. andlever contactB to'the negative terminal 3! oi the source of current.

The'control relay'O will thus: be energized and will move its contact arm. 2| into engagement'with fixed contact 23. A circuit will thereby be completed from terminal 3!], through lever contact I, line conductor 2, the armature H of the'motor M, rectifier 24, field winding [2, con tact arm 21 of switch UN, segment 29, contact 23, contact arm 2|, line conductor and lever contact-8 to the terminal 3|.

The motor M will thus be started into operation to reverse the points and as soon as the point movement has been completed the motor circuit abovedescribed will be interrupted atthe contact arm 21 of the switch UN. V Immediately afterwards the circuit controller V effects V the deenergization of the c'ontrol relay 0 by the interruption of the circuit of the winding i 3 at V the contact arm |6'wl1ereupon the relay contact arm 2| will return'to its normal position out of engagement with either of theVfixed contacts 22, 23 as shown in the drawing. V

A similar'cycle of operations will be performed if the point lever 4 is restored to its normal position N, thecontrol relay being energized by cur rent in the opposite direction, from the terminal 30, through lever contact 5, line conductor rectifier 20, contact segment |8 of circuit controllerV, contact arm- I6, wire i5, relay winding l3, wire l4, line conductor 2 and lever contact upon moved into engagement with fixed contact 7 22'and currentis supplied to the motor M from 6 ductor contact arm'2|,'contact22, contact segterminal 30, through lever contact 5, line con ment 28 of switch UR, contact arm 26, field winding 2,.rectifier 25,'armature line con' ductor 2 and lever contact 5 to terminal 3|. The

motor M is thus rotated in a direction to effect the setting of the points to their normal position'and when this has been completely effected,

V the relay 0 is deenergize'd as above described.

It will be observed that the field winding I2 of the motor M is permanently shunted by a" f be of very light'construction. j

winding 50.

circuit including the two rectifiers 24, 25 connected to one terminal of the motor armature l this circuit constituting a discharge path for'the reactive current generated when the supply of current to the motor 'M is interrupted. The field excitation thus tends to be maintained or prolonged and assists the action of a snubbingf circuit which is preferably provided for the motor armature for each direction of rotation,

this circuitVincluding the armature H, the 'cor responding rectifier 24 or 25, the field winding |2,- a contact 32 or 33 closed by the normal or reverse switch UN or'UR when in its extreme position and a directional switch 34 or 35 which is closed so long as the armature is rotating V in thecorresponding direction. The purpose ofthe directional switch is to prevent short-circuituninterrupted when armature ll comes to a ing of the .armature u through the snubbing standstill, would interfere with the properop- V eration of motor M during a subsequent reversalof the switch S.

It will be noted that the control relay' O is '7 not during any part of the operation of the points required to break a current carrying circuit so that 'the control relay contacts 2|, 22, 23 may Referring now .to the arrangements for indicating the setting of the points at the point of control G, the third line conductor '3 is connected V at the point of control through one winding 36 'V 1 of a point indication relay K of the two-element alternating current type to one or other of the control line conductors |,2through the lever contacts 9 or II! according to whether the point lever 4 is in its normal or reverse position.

At the points an indication controller '3! is provided which is diagrammatically shown as comprising cam members 31, 38 operated by the point tongues and arranged to operate movable) contact arms 39,'40,'4|, 42 which are adapted to Q cooperate with fixed contacts'43, M, 45, 4-5 connected together by a wire 41; The contact arms 7 above referred to are also adapted to cooperate Vwith fixed contacts 48, 49 connected toone terminal of a source of alternating current indito maintain an efiective short-circuit across'the .5 cated as the secondary winding 50 of a transformer T and with fixed contacts 5|, 52 connected indication wires 'for insuring the deenergizationfl of the indication relay K at all times except when I one or the other of cams '31, 38 occupies its proper indicating position.

The line conductor 3 is connected to the con- V V tact arms 40 and 42, the line'conductor being 6 to terminal 3|. "The contact arm 2| is thereconnected through a condenser 53 to the contact arm 39 while the line conductor 2 is connected through a condenser 54 to the contactiarm 4|.

condenser 53, line conductor lever contact 9; relay winding 36, line conductor 3, contact arm 46 and contact 5| to the other terminal; of the 7 When on the other hand the points are fully other terminal of the transformer winding 50 to that above described the circuit of the relay winding 36 being completed through the line conductor 2 and condenser 54 so that the indication given by the relay K is correspondingly reversed. It will be observed that the condensers 53, 54 isolate the source of alternating current utilized for indication from the direct currents in the control line conductors I and 2, while on the other hand the alternating current is. prevented from flowing through the battery or other source of control current. The condensers 53, 54 may if desired be so designed as to produce series resonance in the indication circuits in conjunction with the in ductances of these circuits so as to increase the indication currents flowing and in the event of a condenser becoming short-circuited a marked decrease in the voltage at the indication relay K will result thus causing the release of the relay. It willbe understood that the indication relay K or its equivalent may be arranged to give a continuous indication of the setting of the points or -to control the movement of the point lever 4 to its full normal or release position in the well known manner.

If desired, the arrangements for controlling the point operating mechanism above described may evidently be employed in connection with other arrangements for effecting the indication of their setting involving separate line wires for this purpose.

The invention may be applied to control systems in which two point operating mechanisms are controlled from a single point lever or its equivalent, only a single pair of control line conductors being necessary since the control relay 0 completely isolates each point machine at the end of the point movement.

The invention is evidently not limited to the particular arrangements and connections above described and illustrated by way of example which may be varied in many respects without exceeding the scope of the invention.

Having now particularly described and ascertained the nature of our said invention and in what manner the same is to be performed we declare that what we claim is:

1. In combination with a track switch, a normally deenergized polarized control relay at the track switch location and having a normally open contact which assumes a normal or a reverse position according as said control relay is energized in the normal or the reverse direction respectively, means effective when said contact occupies its normal or reverse position for selectively operating said track switch to its normal or reverse position respectively, means including a lever having a normal and a reverse position for selectively energizing said control relay in the normal or the reverse direction in accordance with the position occupied by said lever, and means automatically effective whenever said track switch and said lever are out of correspondence for energizing said control relay to thereby operate said track switch to a position in agreement with the position of said lever.

2. In combination with a track switch, a normally deenergized polarized control relay having a contact which assumes a normal or a reverse position according as said control relay is energized in the normal or the reverse direction respectively, means efiective when said contact occupies its normal or reverse position for selectively operating said track switch to its normal or reverse position respectively; a lever having-a normal and a reverse position for selectively closing a normal or a reverse energizing circuit for said control relay in accordance with the position occupied by said lever, and a circuit controller governed by said switch and having a first contact included in said normal energizing circuit which first contact remains closed at all times except when the switch occupies its extreme normal position as Well as a second contact included in said reverse energizing circuit which second contact remains closed at all times except when the switch occupies its extreme reverse position, whereby a displacement of the switch from either extreme position causes said control relay to become energized for restoring said switch to a position in agreement with the by said lever.

3. In combination with a. track switch, a normally deenergized polarized control relay having a contact which assumes a normal or a reverse position according as said control relay is energized in the normal or the reverse direction respectively, means effective when said contact occupies its normal or reverse position for selectively operating said track switch to its normal or reverse position respectively, a lever having a normal and a reverse position for selectively closing a normal or a reverse energizing circuit for said control relay in accordance with the position occupied by said lever, a rectifier poled in the normal direction included in said normal .energizing circuit, a rectifier poled in the reverse direction included in said reverse energizing circuit, and a circuit controller governed by said switch and having a first contact included in said normal energizing circuit which first contact remains closed at all times except when the switch occupies its extreme normal position as well as a second contact included in said reverse energizing circuit which second contact remains closed at all times except when the switch occupies its extreme reverse position.

4. In combination with a track switch, an electric motor for operating said switch, a normally deenergized polarized control relay having a contact which assumes a normal or a reverse position according as said control relay is energized in the normal or the reverse direction respectively, a lever having a normal and a reverse position for selectively closing a normal or a reverse energizing circuit for said control relay in accordance with the position occupied by said lever, means comprising a circuit including a first rectifier and also a contact of said lever and effective when said relay contact occupies its normal position for causing current to flow through both the field and armature of said motor in the normal direction whereby said switch is operated to its normal position, and means including a second rectifier and eiiective when said relay contact occupies its reverse position for causing current to flow through said. motor field in the normal direction and through said motor armaturein the reverse direction whereby said switch is operated to its reverse position.

5. In combination with a track switch, an elec tric motor for operating said switch, a normally deenergized polarized control relay having a contact which assumes a normal or a reverse position according as said control relay is energized in the normal or the reverse direction respectively, a lever having a normal and a reverse position for selectively closing a normal or a reverse energizing circuit for said control relay in accordposition occupied motor field in the normal position.

ance with the position occupied by said lever, means including a first rectifier and efiective when said contact occupies its normal position for causing current to fiow through both the field andv armature of said motor in the normal direcin the normal energizing circuit for said control relay which first, contact remains closed at all times except when the switch occupies its extreme normal position as well as a second contact included in said reverse energizing circuit which second contact remains closed at all times except when said switch occupies its extreme, reverse 6. In combination with a track switch,.an elec trio motor for operating said switch to its normal or reverse position according as said motor is energized in the normalor the reverse direction respectively, meansfor at times closing a normal'energizing circuit for said'motor and for at other times closing a reverse energizing circuit for said motor, a circuit controller governed by said switch and having a first contact included in said normal energizing circuit which first contact remains closed at all times except when the switch occupies its extreme normal position as well as a second contact included in said reverse energizing circuit which second contact remains closed at.

all times except when the switch occupies its extreme reverse position, a first and a second 7 snubbing contact closed by said controller when the switch occupies its extreme normal and its extreme reverse position respectively, and a directional switch governed by said motor. and effective provided'said motor is rotating in the normal direction for closing a first snubbing circuit' through said first snubbing contact and effective provided'said motor is rotating in the reverse direction for closing a second snubbing circuit through said second, snubbing contact.

RODERICK 'MARCUS MACGREGOR. DOUGLAS GOLDIE SHIPP. 

